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Title: The LSST Camera Overview

Abstract

The LSST camera is a wide-field optical (0.35-1um) imager designed to provide a 3.5 degree FOV with better than 0.2 arcsecond sampling. The detector format will be a circular mosaic providing approximately 3.2 Gigapixels per image. The camera includes a filter mechanism and, shuttering capability. It is positioned in the middle of the telescope where cross-sectional area is constrained by optical vignetting and heat dissipation must be controlled to limit thermal gradients in the optical beam. The fast, f/1.2 beam will require tight tolerances on the focal plane mechanical assembly. The focal plane array operates at a temperature of approximately -100 C to achieve desired detector performance. The focal plane array is contained within an evacuated cryostat, which incorporates detector front-end electronics and thermal control. The cryostat lens serves as an entrance window and vacuum seal for the cryostat. Similarly, the camera body lens serves as an entrance window and gas seal for the camera housing, which is filled with a suitable gas to provide the operating environment for the shutter and filter change mechanisms. The filter carousel can accommodate 5 filters, each 75 cm in diameter, for rapid exchange without external intervention.

Authors:
; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
897454
Report Number(s):
SLAC-PUB-12291
TRN: US200705%%251
DOE Contract Number:
AC02-76SF00515
Resource Type:
Conference
Resource Relation:
Conference: To appear in the proceedings of SPIE Conference on Ground-Based and Airborne Instrumentation, Orlando, Florida, 24-31 May 2006
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CAMERAS; CRYOSTATS; PERFORMANCE; SAMPLING; SHUTTERS; TELESCOPES; TEMPERATURE GRADIENTS; ASTROPHYSICS; DESIGN; Accelerators,ASTRO

Citation Formats

Gilmore, Kirk, Kahn, Steven A., Nordby, Martin, Burke, David, O'Connor, Paul, Oliver, John, Radeka, Veljko, Schalk, Terry, Schindler, Rafe, and /SLAC. The LSST Camera Overview. United States: N. p., 2007. Web.
Gilmore, Kirk, Kahn, Steven A., Nordby, Martin, Burke, David, O'Connor, Paul, Oliver, John, Radeka, Veljko, Schalk, Terry, Schindler, Rafe, & /SLAC. The LSST Camera Overview. United States.
Gilmore, Kirk, Kahn, Steven A., Nordby, Martin, Burke, David, O'Connor, Paul, Oliver, John, Radeka, Veljko, Schalk, Terry, Schindler, Rafe, and /SLAC. Wed . "The LSST Camera Overview". United States. doi:. https://www.osti.gov/servlets/purl/897454.
@article{osti_897454,
title = {The LSST Camera Overview},
author = {Gilmore, Kirk and Kahn, Steven A. and Nordby, Martin and Burke, David and O'Connor, Paul and Oliver, John and Radeka, Veljko and Schalk, Terry and Schindler, Rafe and /SLAC},
abstractNote = {The LSST camera is a wide-field optical (0.35-1um) imager designed to provide a 3.5 degree FOV with better than 0.2 arcsecond sampling. The detector format will be a circular mosaic providing approximately 3.2 Gigapixels per image. The camera includes a filter mechanism and, shuttering capability. It is positioned in the middle of the telescope where cross-sectional area is constrained by optical vignetting and heat dissipation must be controlled to limit thermal gradients in the optical beam. The fast, f/1.2 beam will require tight tolerances on the focal plane mechanical assembly. The focal plane array operates at a temperature of approximately -100 C to achieve desired detector performance. The focal plane array is contained within an evacuated cryostat, which incorporates detector front-end electronics and thermal control. The cryostat lens serves as an entrance window and vacuum seal for the cryostat. Similarly, the camera body lens serves as an entrance window and gas seal for the camera housing, which is filled with a suitable gas to provide the operating environment for the shutter and filter change mechanisms. The filter carousel can accommodate 5 filters, each 75 cm in diameter, for rapid exchange without external intervention.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Jan 10 00:00:00 EST 2007},
month = {Wed Jan 10 00:00:00 EST 2007}
}

Conference:
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  • Meeting the science goals for the Large Synoptic Survey Telescope (LSST) translates into a demanding set of imaging performance requirements for the optical system over a wide (3.5{sup o}) field of view. In turn, meeting those imaging requirements necessitates maintaining precise control of the focal plane surface (10 {micro}m P-V) over the entire field of view (640 mm diameter) at the operating temperature (T {approx} -100 C) and over the operational elevation angle range. We briefly describe the hierarchical design approach for the LSST Camera focal plane and the baseline design for assembling the flat focal plane at room temperature.more » Preliminary results of gravity load and thermal distortion calculations are provided, and early metrological verification of candidate materials under cold thermal conditions are presented. A detailed, generalized method for stitching together sparse metrology data originating from differential, non-contact metrological data acquisition spanning multiple (non-continuous) sensor surfaces making up the focal plane, is described and demonstrated. Finally, we describe some in situ alignment verification alternatives, some of which may be integrated into the camera's focal plane.« less
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